Apparatus for building tires

ABSTRACT

Apparatus for applying tread rubber to bases of circular cross section, which comprises a central shaft, means for mounting a plurality of bases on the central shaft, means for rotating said shaft to advance the bases through a succession of stations, means mounted adjacent one of said stations for applying rubber to a base advanced to said stations, means mounted adjacent another of said stations for applying rubber to the base having the rubber thereon applied thereto at said one of said stations, the rubber applied at the two stations taken together forming the tread and sidewall rubber portions of a tire, and means mounted on said central shaft for stitching the rubber applied to the base at said one of said stations firmly to the base.

United States Patent [191 Rattray Nov. 27, 1973 APPARATUS FOR BUILDINGTIRES Primary Examiner-Al fred L. Leavitt [75] Inventor. gllilam L.Rattray, Garden Grove, Assistant Examiner c B. Cosby AttorneyGeorge W.Price and Barry H. Fishkin [73] Assignee: AMF Incorporated, WhitePlains,

57 ABSTRACT [22] Filed: 1971 Apparatus for applying tread rubber tobases of circu- [2 Appl 119,5 3 lar cross section, which comprises acentral shaft, means for mounting a plurality of bases on the centralshaft, means for rotating said shaft to advance the [52] US. Cl 156/396,156/406, 156/409 bases through a Succession of stations means mounted[51] '3 Bzgh 17/08 132% 17/10 B2911 17/37 adjacent one of said stationsfor applying rubber to a [58] Field of Search 156/394, 111, 130, baseadvanced to Said Stations means mounted adja 156/396 41 413 cent anotherof said stations for applying rubber to the base having the rubberthereon applied thereto at said [56] References cued one of saidstations, the rubber applied at the two sta- U ITED STATES PATENTS tionstaken together forming the tread and sidewall 2,208,324 7 1940 Haase156/396 rubber p n of a tire, a m a s m unted on said 3,539,415 11/1970Du Bosque 156/397 central shaft for stitching the rubber applied to the3,223,573 12/1965 Deist 156/130 X base at said one of said stationsfirmly to the base. 2,340,267 l/l944 Haase 156/406 X 2,671,495 3 1954lredell 156/406 x 3 Chums, 7 Drawmg Flaures PATENTEDNDVZYIBH 3.7751220SHEET 10F G ATTORNEY PATENTEDNBVZTWS 3.775.22U SHEET 2 UP 6 INVENTOR.

W IL LIAM L. RATTRAY ATTORNEY PATENTEDHUYZHQB 3.775.220

SHEET 30F 6 FIG. 5

5 I NVENTOR.

WILLIAM L. RATTRAY FIG.

ATTORNEY PATENTEDNUV 27 I973 SHEET H 0F 6 INVENTOR.

WlL LIAM L. RATTRAY @95 ATTORNEY PATENTEU am 2 1 ma SHEET 5 BF 6INVENTOR WILLIAM L. RATTRAY ATTORNEY FIG. 7.

INVENTOR WILLIAM L. RATTRAY ATTORNEY APPARATUS FOR BUILDING TIRESBACKGROUND This invention relates to apparatus for applying rubber to abase and more particularly to an automatic apparatus for applying astrip of rubber in a predetermined pattern to a succession of tirecarcasses mounted on building drums.

The art of tire making has attained a certain maturity in that large andhigh volume apparatus have been developed and perfected. However, thisapparatus generally suffers from severe problems in the materialhandling aspects of the machines, that is the storage and utilization ofrubber prior to and in the tire building process, and still involves agreat deal of hand labor. More specifically, the present day operationinvolves shaping and joining the tread and sidewall at a location otherthan that where the tire is completed. There is usually one largeextruder comples which makes all of the tread and sidewall stock for theentire plant. The treads and sidewalls are extruded to shape, joined andthen cut to specified lengths for the particular tires which they willgo on. These slabs of rubber are then inventoried in a specialbook-shelf type of portable rack which keeps eachpiece of rubberseparate from the rest.

The slab of rubber is cut toa length equal to one circumference of thetire so that the final, tire building, operation involves wrapping theslab around the tire carcass one time to make a butt joint. The crucialfactor in this operation is in the butt jointing operation. Since theslabs of rubber, although cut to a precise length at the extruder line,will vary some due to rubber variations, the intelligence and judgmentof a manual laborer is required to compensate for these lengthvariations when the slab is applied to the tire carcass.

The instant apparatus solves the above problems by utilizing rubber instrip form, which can be supplied by a smaller extruder, and applyingthe strip in a series of turns of a circular base to form the rubbercovering of a tire or similar article. The width and depth of the rubbercovering is easily adjustable by controlling the number of and spacingbetween sucessive strips applied to the base.

However, previous strip winding apparatus have also involved someproblems that inhibited its application to new tire manufacture. One ofthese problems has been air bubbles caught between adjacent strips ofrubber, and in the fact that the strip winding process still requiredmanual labor to start and stop the process that is, the strip had tofirst be applied to the carcass by hand and at the end of the operation,the end of the strip had to be hand severed from the supply.

In addition, it was difficult to fabricate articles such as tires whichrequired the application of two types of rubber to a base by the stripwinding process, since existing processes necessitated that the tires bemade on two machines, or in shifts on the same machine.

SUMMARY It is therefore an object of this invention to provide animproved tire building method and apparatus utilizing strip rubber.

It is further object of the invention to provide apparatus wherein twotypes of rubber may be rapidly and readily applied in strip form to acircular base in a desired pattern.

It is still a further object of this invention to provide tire buildingapparatus with an improved stitching assembly for better adherence ofthe rubber to a tire carcass.

It is yet another object of this invention to provide in a tire buildingapparatus an improved rubber application assembly adapted to initiateand terminate the rubber building process without manual assistance.

DESCRIPTION OF THE DRAWINGS FIG. 1 is an end elevation view of the mainportion of the apparatus according to the invention.

FIG. 2 is a plan view of the apparatus shown in FIG. 1.

FIG. 3 is a side elevation view of a rubber application head assemblyfor that forms part of the apparatus shown in FIGS. 1 and 2.

FIG. 4 is a plan view of the assembly shown in FIG. 3.

FIG. 5 is a sectional view of an application roller, taken along line 55of FIG. 4.

FIG. 6 is a side elevation view of a power stiching assembly that formspart of the apparatus shown in FIGS. 1 and 2.

FIG. 7 is an end view of the assembly shown in FIG. 6.

DESCRIPTION OF THE PREFERRED EMBODIMENT For purposes of simplicity apreferred embodiment of the invention is shown and described herein asapplying rubber directly to circular tire carcasses. However, it shouldbe clear to those skilled in the art that the apparatus and method setforth hereinbelow are also applicable to the application of rubber toother circular bases.

With reference to the drawings, apparatus according to the invention maycomprise a frame 10 having opposed mounting brackets 12 adapted torotatably support a shaft 14 therebetween. A rectangular mounting plate16 is mounted at one end of shaft 14 and is rotatable therewith.

A mounting assembly 18 including a drum 19 is mounted at each of thefour comers of the rectangular plate 16. The drums 19 are collapsible bythe mounting assemblies 18 for receiving tire carcasses and expandibleto securely mount the carcasses thereon.

Each of the drums 19 is rotatable by a shaft 20 connected to a motor 22by a suitable gear reduction assembly 24.

The motors 22 are operable to drive each shaft 20 at a plurality ofspeeds. A hydraulic motor 25 is provided for indexing the shaft 14through a 360 cycle in increments, each drum 19 thus being moved forfour stations, designated 26, 28, 30 and 32 respectively. A Fergusondrive system 33 is provided between motor 2S and the shaft 14 so thatprecise ninety degree increments of rotation can be made.

At the first station, 26, tire carcasses are manually placed on andremoved from the apparatus in conjunction with actuation of the mountingassembly 18. The second station, 28, is a rubber building stationwhereat a rubber application assembly 34 applies strip rubber suppliedfrom an extruder (not shown) to the tire carcass which has been advancedthereto and is being rotated by the respective motor 22. The thirdstation, 30, is a dwell station whereat the rubber applied at station 28is allowed to cool and at the fourth station, 32, a second rubberapplication assembly 36 applies strip rubber of a different type,supplied from a second extruder (not shown), to the tire carcass whichhas been advanced thereto and is being rotated by the respective motor22.

A power stitching assembly 38 is mounted on hub 14 for movement intoengagement with the drums at the second and fourth station for firmlystitching the rubber strips applied thereto together and to the carcass.

The rubber strips applied to the rotating carcasses by the applicationassemblies 34 and 36 are supplied from two conventional strip rubberextruders, each providing a strip substantially of constant crosssection at a substantially constant rate. The rate of feed of theextruder is approximately equal to the angular velocity of the rotatingdrum. Each strip is guided to its respective application assembly by aplurality of idler rollers 39 and a roller 40 mounted on a dancer arm41.

The dancer arm 41 is connected to a rotary potentiometer (not shown)coupled to the control circuit for each of the motors 22. Thus theangular velocity of the spinning drum is variable in response toextruder output variation to avoid rubber strip starvation or glut.

Each of the rubber application assemblies 34 and 36 (FIGS. 3 and 4) aremounted on a carriage 42 for movement along a frame 44 positioned alongthe axis of the respective drums at the second and fourth stations.Since the rubber application assemblies, carriages and frames for thesecond and fourth stations are identical, only those for the fourthstation will be set forth in detail hereinbelow, it being understoodthat the rubber application assembly, carriage and frame for the secondstation will be identical and facing in the opposite direction.

With reference to FIG. 1, the frame 44 includes a pair of verticallyspaced shafts, 46 and 48 and a threaded rod 50 mounted in parallelspaced relationship thereto and positioned therebetween. The frame 44 isconnected to frame by a bracket 51.

The carriage 42 is mounted on the shafts 46 and 48 and rod 50. Thecarriage (FIG. 3) comprises a horizontal base 54 with a bracket 56depending therefrom, a pair of spaced vertically extending members 58mounted thereon and a vertically extending cross member- 59 connectedbetween the back of members 58.

A pair of recesses, 60 and 62, are provided in bracket 54 for receivingthe rods 46 and 48 respectively and an internally threaded boss 64 isprovided for accepting the threaded rod 50. The carriage is driven alongthe shafts 46 and 48 and rod 50 by the rotation of the threaded rod byan electric motor 66, which is mounted at one end of the rod and inaxial alignment therewith.

The rubber application assembly 34 comprises an application roller 68mounted for pivotal movement toward and away from the tire carcass on apivoting assembly 70 and a plurality of stitching rollers 72 mounted forpivotal movement toward and away from the drum on a pivoting assembly74. A transposition roller 76 and a directing roller 78 are included inthe assembly 34 for guiding strip rubber from the idler rollers 39 tothe application roller 68.

More specifically, the application roller'pivoting assembly 70 includesa pair of spaced vertically extending members, 80 and 82, and verticaland horizontal cross plates 84 and 86 respectively, which join in thevertical members 80 and 82 adjacent the tops thereof.

The assembly 70 is mounted for its pivotal movement on a shaft 92 thatis mounted between the vertically extending carriage members and ispivoted on shaft 92 by an air cylinder 94, which includes a piston rod96 extending therefrom. The piston rod includes a forked end member 98which is connected to a lug 100 off vertical plate 84. The other end ofair cylinder 94 is connected to. the cross member 59 by a resilientconnection 102.

The resilient connection 102 includes a lug 104 extending from the aircylinder and a double bracket 106 pivotally connected to the member 59at 108 and extending upwardly therefrom to a position whereat its twomembers are positioned on either side of the lug 104, whereat a bolt 110connects the lug and the double bracket 106. A pin 112 is mounted acrossthe double bracket 106 and a rod 114 is mounted in cross member 59 inposition to engage the pin 112. A spring 116 biases pin 112 and thusbracket 106 away from the cross member 59.

A sequence switch 120 having an actuator button 121 is mounted to anupright member 58. An actuator member 122 is mounted on air cylinder 94in spaced relationship with the button 121.

In operation, upon actuation of the air cylinder 94, the piston rod 96is extended and the pivoting assembly 70 and thus application roller 68is advanced from the retracted position to the position shown in FIGS. 1and 3, whereat the application roller is adjacent the tire carcass. Inthe latter position, rubber strip on the application roller will betransferred to the drum upon the rotation of the latter.

Actuation of the air cylinder, in addition to driving the applicationroller 68 to the drum, will cause the cylinder body to pivot bracket l10in a clockwise direction, causing the actuator 122 to engage button 121of the sequence switch 120.

The sequence switch is connected to the control circuits for theextruder and the motor 22. With the actuation of the sequence switch theextruder will start and the motor 22 will start, spinning the drum.After an interval predetermined by the time required to allow the drumto reach a predetermined angular velocity, the air cylinder 94 isde-activated and the application roller 68 is retracted, serving toguide the strip to the spinning carcass.

With reference to FIG. 5, the application roller 68 is provided with arecess 123 therein. The roller is mounted for free rotation on a shaft124 that is supported by a bracket 125 mounted on the vertical crossplate 84 of the pivoting assembly 70. A magnetic brake 126 is mounted toa bracket 128 that is mounted to the cross plate 84 in spacedrelationship with bracket 125. The brake 126 extends from bracket 128into the recess 123 in the application roller 68 and is operable to stopthe rotation of the roller upon the actuation thereof.

The stitching rollers pivoting assembly 74 includes a shaped verticallyextending member 130 mounted on a shaft 132 that is pivotally mountedbetween a pair of brackets 134 positioned on horizontal base 54. Astitcher support housing 136 is mounted for free pivotal movement abouta rod 138 mounted to the support member 130 by a cantilevered horizontalbar 140. Each stitching roller 72 is mounted for free rotation on ashaft 142 supported on a horizontally extending arm 144. The arms 144are mounted in the support 136 and are biased outwardly toward the drumby springs 146. The independent mounting of the stitching rollers 72 andthe pivotable mounting of the support housing 136 provide capability forthe stitching rollers to conform to and remain in pressing contact withthe rubber on the tire carcass as the assemblies 34 and 36 are indexedalong the axis of the drum.

The stitching roller pivoting assembly is pivoted by an air cylinder 150that is pivotally connected at one end thereof to a bracket 152 by apivotal connection 154 located on the lower portion of cross member 59.The pivotal connection 154 includes a forked shaped lug 156 mounted onthe air cylinder, a bracket 158 mounted on the cross member andextending between the tires of the fork shaped lug and a pin 160 passingthrough the bracket and the lug. A piston rod 162 extends from the otherend of air cylinder 150 and is pivotally connected to the support 140 at164. In operation, upon actuation of the air cylinder 150, which isactuated simultaneously with air cylinder 94, the stitching rollers willbe advanced from a retracted position to the extended position adjacentthe drum shown in FIGS. 1 and 3. The stitcher rollers remain in contactwith the rubber on the drum after the applicator roller is retracted.

The directing roller 78 is mounted for free rotation on a shaft 170 thatis cantilevered from a bracket 172. The bracket 172 is welded to ashaped bracket 174 that is mounted to one of the vertically extendingmembers 58 by screws 176. The transposition roller 76 is mounted forfree rotation on a shaft 178 that is cantilevered from an arm 180 thatis pivotally mounted to shaped bracket 174 at 182. a

The transposition roller 76 is mounted for movement along with theapplication roller 68 by a linkage 184 connecting arm 180 and verticallyextending support 82. The linkage 184 includes a lug 186 mounted on arm180, a link 188 having fork shaped members 190 and 192 on either endthereof, a pin 194 connecting the fork shaped member 190 to the insidewall of vertical member 82 and a pin 196 connecting fork shaped member192 to lug 186. Thus, upon actuation of air cylinder 150 both theapplication roller 68 and the transposition roller 76 will be withdrawnwith respect to the drum.

A guide member 200 is mounted on horizontal plate 84 to guide the stripof rubber from the transposition roller 76 to the application roller 68.The guide member is connected to the plate by a pair of screws 202 thatpass through slots 204 in a flange of the guide member such that theposition of the guide may be positioned for varying rubber strip widths.

A sensing roller 206 is mounted just above the application roller 68 bya rod 208 cantilevered from an arm 210 that is pivotally connected tothe inside wall of vertical support 82 at 212. A linear voltagedifferential transducer 214 is mounted inside the vertical support 82,and coupled to arm 210. The sensing roller 206 rides on the rubber strippassing over the application roller 68 and the thickness of the strippassing thereunder is determined by the transducer in accordance withthe angular position of the arm 210. The signal from the transducer isutilized to monitor the thickness of the rubber strip and display theribbon thickness on a gauge (not shown) displayed on the extrudercontrol.

A photocell 218 is mounted in the vertical support 80 and acorresponding member 220 is mounted in vertical support 82 to receivethe beam. The beam will make when the pivoting assemblies and 74 haveretracted both the application roller 68 and the stitching rollers 72.

With reference to FIGS. 6 and 7, the power stitching assembly 38includes a sleeve 225 mounted for slidable movement on shaft 14 and apair of slitching heads 228 and 230 mounted on sleeve 225 and extendingtoward a respective one of the second station 28 and fourth station 32.

Each of the stitching heads 228 and 230 comprises a pair of horizontalbeams 232 and 234 extending from the sleeve 225 adjacent the endsthereof. A mounting bracket 236 is affixed to the end of each of thebeams 232 and 234 and a rod 240 is mounted between the brackets 236. Aplurality of arms 242 are pivotally mounted to the rods 240 and astitching roller 244 is mounted for free rotation on the end of each ofthe arms 242.

Each of the arms 242 is pivoted by an air cylinder 246 mounted betweenthe sleeve 225 and the arm. Each cylinder is pivotally connected to abracket 248 bolted to the sleeve, as at 250. A piston rod 252 extendsfrom the other end of each of the air cylinders and is pivotallyconnected to the respective stitching roller arms at 254. A pair of airhoses 256 and 258 are connected to the respective ends of each of theair cylinders and actuate the piston rod outward and inward respectivelyin the air cylinder. The air hoses 256 are all supplied from an airmanifold 260 mounted between the horizontally extending beams 232 and234 and the air hoses 258 are actuated from another air manifold 262mounted between the horizontally extending beams in parallel spacedrelationship with the air manifold 260.

The outward stroke of the piston rods 252 drive the stitching rollersinto engagement with the rubber applied to the respective drums at thesecond and fourth stations and the inward stroke returns the stitchingrollers to their inactive positions shown in FIGS. 1, 2, 6 and 7.

The sleeve 225 is slidable on shaft 14 and is driven therealong by aSaginaw screw 264 mounted in spaced relationship with the shaft 14 andthreadedly mounted in a Saginaw nut 226 that is bolted to the sleeve bybolts 268. The Saginaw screw is powered by a reversible DC. motor (notshown) such that the sleeve is movable along the shaft in bothdirections. The amplitude of the movement of the sleeve is slightlygreater than the distance between the stitching rollers so that thestitchers cover a broad area of the drums. The sleeve is driven in afirst direction to power stitch and is driven backward to its startposition during the ninety degree indexing operation at the end of thestep.

In operation, the apparatus is controlled by a logic system includingpunched tape control for the configuration of rubber applied by theapplication assemblies. More specifically, in a typical sequence a tirecarcass is loaded on a collapsed drum 19 at first station 26 and themounting assembly 18 is actuated to expand the drum to securely mountthe drum thereon. At a predetermined time, the operation of motor 25 isinitiated and the Ferguson drive 33 indexes the drum 19 to the secondstation 28. The rubber application assembly 34 mounted at the secondstation is then actuated. This involves the actuation of air cylinders94 and 150, which drives the application roller 68 and the stitchingrollers 72 into position adjacent the drum. A strip of rubber is leftextending from the extruder to the application roller at the end of eachrubber application cycle, so that when the next cylinder 94 is actuatedat the start of the next cycle the end of the rubber strip will bedriven into engagement with the tire carcass on the drum by theapplication roller.

The actuation of air cylinder 94 also actuates the sequence switch 120to start the extruder feed and actuate motor 22 to spin the drum. Therotary movement of the tire carcass on the drum picks the rubber stripfrom the application roller. After a predetermined time delay to allowthe ribbon to be properly attached to the tire carcass, the air cylinder94 is de-activated and the application roller swings back to a positionspaced from the drum, where it serves to guide the rubber strip thereto.

The rubber application assembly carriage 42 is then indexed down theframe 44 by motor 66 in accordance with a pattern predetermined by thepunched tape whereupon a series of overlapping layers is wrapped aboutthe drum in a predetermined pattern.

After the rubber application assembly has applied the first length ofrubber to the tire carcass on the drum, the punched tape controlactuates the brake 126, breaking the strip at the application roller,halts the extruder feed, de-activates the motor 22, and retracts thestitching rollers 72. This leaves the strip extending from the extruderto the application roller in preparation for the next rubber applicationcycle. The application roller is then driven down the drum axis to thepredetermined point where the application of the second length of rubberis to be initiated and the sequence described hereinabove is repeated.

At the end of the second rubber application sequence, when the stitcherunit 74 is driven back by air cylinder 150, the making of the light beamprovided by photocell 218 prepares the control circuit for the powerstitching sequence and actuates motor 66 to drive the applicationassembly back down frame 44 to its start position.

The initiation of the power stitching sequence involves the supplying ofair through the air manifold 260 and the air hoses 256 to drive thepiston rods 252 outwardly. This causes the stitching rollers 242 toengage the rubber just applied to the rotation drum. At the same time,the drum is spun at a higher angular velocity. The motor driving theSaginaw screw 264 is then actuated and the sleeve 225 is driven down theshaft 14 a distance slightly greater than the distance between thestitching rollers. The combination of the pressure, of the stitchingrollers 242, high speed drum rotation and lateral movement of thestitching rollers provides a strong force pressing the rubber stripstogether and against the tire carcass to remove air from the interfacesbetween the strips and between the strips and the drum.

At the end of the power stitching sequence, the stitching rollers aredriven back to their inactive position by supplying air through manifold262 and air hoses 258 to the air cylinders 246. The Saginaw screw thendrives the sleeve 225 back to its start position and the motor 25 isthen pulsed again by the punched tape control and the drum is driven 9Qdegrees to the third station 30 whereat it is allowed to dwell to permitthe rubber thereon to cool.

At the end of the dwell period the motor 25 is pulsed to drive the drumto the fourth station 32 whereat the rubber application assembly 36 isactuated by the punched tape control. The rubber application assembly 36operates in a mode identical to the rubber application assembly 32.However, a different type of rubber is applied to the tire carcass onthe drum at the fourth station and the punched tape program directs therubber to the middle portion of the drum not covered at the secondstation. At the termination of the rubber application sequence the powerstitching sequence is again initiated to firmly adhere the rubber to thetire carcass.

At the conclusion of the power stitching sequence the motor 25 is againpulsed and the drum is rotated back to the first station where the drumis collapsed by actuation of the mounting assembly 18 enabling thecarcass to be removed therefrom and a new carcass placed thereon,preparatory to a new 360 cycle.

Of course, the plate 16 mounts four drums 19 so that four drums arebeing operated upon at any given moment and while one drum is at thesecond station having rubber applied to the tire carcass thereon, a drumat the fourth station for the application of the remainder of the rubberthereon and the power stitching assembly is provided with two stitchingheads such that the rubber on the tire carcasses at the second andfourth stations are power stitched at the same time.

Having now fully set forth both structure and operation of preferredembodiments of the concept underlying the present invention, it may bethat various other embodiments as well as certain variations andmodifications of the embodiments herein shown and described will occurto those skilled in the art upon becoming familiar with said underlyingconcept. All such embodiments, variations, and modifications andincorporate the spirit of the invention and depend upon its underlyingconcept are consequently to be considered as within the scope of theclaims appended herebelow, unless the claims by their language expresslystate otherwise.

We claim: 1. Apparatus for applying tread rubber to bases of circularcross-section, which comprises:

a central shaft, means for rotatably mounting a plurality of bases onsaid central shaft at positions spaced radially and circumferentially ofthe axis of said shaft and with the axes of rotation of said mountingmeans generally parallel to the axis of said central shaft,

means for rotating said shaft to advance the bases through a successionof stations disposed in circumferentially spaced relation around andradially spaced relation to the axis of said shaft,

means mounted adjacent one of said stations for applying a first portionof rubber to bases advanced thereto, means mounted adjacent another ofsaid stations for applying a second portion of rubber to a base,advanced thereto with a first portion of rubber thereon, and a sleevemounted co-axially with said central shaft and for movement axiallythereof plurality of rotatable stitching rollers mounted on said sleevefor movement therewith and in radially spaced relation to said axis withone of said rollers adjacent to said one of said stations and another ofsaid rollers adjacent to said other of said stations, both of said oneroller and said other roller having its axis of rotation intermediatethe axis of said central shaft and the axis of the mounting means at thestation to which it is adjacent, means for driving said one stitchingroller into engagement with the rubber on the base located at said onestation and for driving said other stitching roller into engagement withthe rubber on the base located at said other station, means for spinningsaid bases around the axes of said mounting means therefor located atboth one station and said other station, and a single means for drivingsaid sleeve axially of said central shaft to cause both said one rollerand said other roller mounted thereon to move in a direction parallel tosaid axis of said central shaft and thereby simultaneously to moveacross the rubber on the bases at both said one station and said otherstation and to firmly stitch the rubber on said bases thereto.

2. Apparatus according to claim 1, further comprising:

means for feeding a strips of rubber, and

means for directing the strip of rubber from the supplying means to therubber application means.

3. Apparatus according to claim 1, wherein said means for applying afirst portion of rubber applies said last portion of rubber to the baseadvanced to said one station in a series of overlapping turns inaccordance with a first predetermined profile and said means forapplying a second portion of rubber applies said second portion ofrubber to the base advanced to said other station in a series ofoverlapping turns in accordance with a second predetermined profile andwherein the predetermined profiles of rubber applied at said one of saidstations and said another of said stations taken together constitute thetread and sidewall rubber portion ofatire.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No.3,775,220 I I Dated November ,1973

Inventor(s) William L. Rattraj It is certified that error appears in theabove-identified patent and that said Letters Patent are herebycorrected as shown below:

Claim 1, column 9, line 2h, after "both insert the word said Signed andsealed this 30th day of April 1971;.

(SEAL) Attestz,

EDWARD I LFLETCHEHJR. C. MARSHALL DANN Attesting Officer Commissioner ofPatents FORM PO-1050 (10-69) USCOMM'DC 60376-P69 a u.s GOVERNMENTPRINTING OFFICE nu o-see-saa.

1. Apparatus for applying tread rubber to bases of circularcross-section, which comprises: a central shaft, means for rotatablymounting a plurality of bases on said central shaft at positions spacedradially and circumferentially of the axis of said shaft and with theaxes of rotation of said mounting means generally parallel to the axisof said central shaft, means for rotating said shaft to advance thebases through a succession of stations disposed in circumferentiallyspaced relation around and radially spaced relation to the axis of saidshaft, means mounted adjacent one of said stations for applying a Firstportion of rubber to bases advanced thereto, means mounted adjacentanother of said stations for applying a second portion of rubber to abase, advanced thereto with a first portion of rubber thereon, and asleeve mounted coaxially with said central shaft and for movementaxially thereof a plurality of rotatable stitching rollers mounted onsaid sleeve for movement therewith and in radially spaced relation tosaid axis with one of said rollers adjacent to said one of said stationsand another of said rollers adjacent to said other of said stations,both of said one roller and said other roller having its axis ofrotation intermediate the axis of said central shaft and the axis of themounting means at the station to which it is adjacent, means for drivingsaid one stitching roller into engagement with the rubber on the baselocated at said one station and for driving said other stitching rollerinto engagement with the rubber on the base located at said otherstation, means for spinning said bases around the axes of said mountingmeans therefor located at both one station and said other station, and asingle means for driving said sleeve axially of said central shaft tocause both said one roller and said other roller mounted thereon to movein a direction parallel to said axis of said central shaft and therebysimultaneously to move across the rubber on the bases at both said onestation and said other station and to firmly stitch the rubber on saidbases thereto.
 2. Apparatus according to claim 1, further comprising:means for feeding a strips of rubber, and means for directing the stripof rubber from the supplying means to the rubber application means. 3.Apparatus according to claim 1, wherein said means for applying a firstportion of rubber applies said last portion of rubber to the baseadvanced to said one station in a series of overlapping turns inaccordance with a first predetermined profile and said means forapplying a second portion of rubber applies said second portion ofrubber to the base advanced to said other station in a series ofoverlapping turns in accordance with a second predetermined profile andwherein the predetermined profiles of rubber applied at said one of saidstations and said another of said stations taken together constitute thetread and sidewall rubber portion of a tire.